Recipe Cards: Useful or Outdated?

I love the idea of collecting my favorite recipes on adorable cards, complete with the amendments I make to the ingredient lists and instructions. Every time I see a cute set of recipe cards my heart skips a beat, but I've never actually purchased a set because I'm not quite convinced they'd be used. So, I wonder...

Are recipe cards useful or outdated?

Related: Online Recipe Card Maker: Beautify and Unify!

(Image: Etsy seller InvitaPaperStudio)